The Most Irreplaceable Sites On Earth

In honour of World Environment Day, held each year on June 5, we are taking another look at the most irreplaceable sites on earth, identified in a study published in Science last year.

In that report, scientists listed more than 100 irreplaceable environments or regions where many animal and plant species cannot be found anywhere else on our planet.

A total of 137 sites were selected from 173,000 protected areas, regions that cover 13% of the earth’s landmass. These are some of the most biologically rich ecosystems in the world but face continued threats and are often poorly managed.

The top sites were the result of two combined rankings: irreplaceability for threatened species and irreplaceability for all — threatened and nonthreatened — species.

Each protected area was analysed individually. But sometimes the regions overlap, effectively protecting the same species. For this reason, researchers combined adjacent or overlapping protected areas into 78 clusters around the world.

Here are some of the most irreplaceable areas from 10 different clusters. Bringing attention to these places is critical to preventing extinctions of the world’s mammals, birds, and amphibians.

The flat-topped mountains of Canaima National Park in southeastern Venezuela are among the world's most ancient rock formations and were the inspiration for Sir Arthur Conan Doyle's adventure novel 'The Lost World.' Canaima is also home the world's highest waterfall, Angel Falls, which is 15 times taller than Niagara Falls at 3,212 feet.

Misty clouds float by in Canaima National Park's Kukenan mesa, a sacred plateau known as Matawi Tepuy to Pemon Indians who believe the dead live there.

The Wet Tropics of Queensland cover roughly 3,500 square miles of Australian forest. Thirteen mammals that live in the Wet Tropics are found nowhere else in the world. This includes the green ringtail possum and kangaroo rats.

The Palawan Game Refuge and Bird Sanctuary in the Philippines is home to the endangered Palawan horned frog, the vulnerable Palawan peacock-pheasant, and the critically endangered Philippine cockatoo. Unfortunately, the natural forest is being destroyed by mining and palm-oil production.

The Palawan peacock-pheasant.

Sierra Nevada De Santa Marta, a mountain refuge for hundreds of species, is located in northern Colombia on the Caribbean coast. More than 600 bird species are found in this region, including the rusty-headed spinetail and white-lored warbler, which can't be found anywhere else on the planet. Certain amphibians and reptiles that live above 9,900 feet are also only found in this part of the world. The nature reserve faces threats from encroaching populations and illegal drug cultivation.

The Atsinanana rain forest in Madagascar is an important habitat to at least 25 species of lemur, including the critically endangered silky sifaka. The animal's biggest threats come from illegal logging and hunting.

Between the mainland of Mexico and Baja California is a region known as the Islands and Protected Areas of the Gulf of California. The gulf was described by Jacques Cousteau as the 'world's aquarium,' but now faces pressure from climate change, commercial fishing, and pollution. The waters are home to the world's smallest and most endangered porpoise, the vaquita. It's also an important breeding ground for the blue whale, the world's largest animal.

A blue whales comes to the surface along the California coast.

The La Amistad-Talamanca Highlands, managed by Costa Rica and Panama, is the largest nature reserve in Central America. Most of the area is covered by tropical rain forests. The region contains at least 90% of Costa Rica's plant species and is home to diverse wildlife, including the ocelot, the central American squirrel monkey, and the giant anteater.

Here's why animals need protection.

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